THis sort of radio, known as an "All American Five" AA5, used pretty much the same schematic. I have such a schematic at my page
http://www.geocities.com/wa2ise/ and scroll about halfway down. One diagram shows the octal tubes yours uses.
A 0.02 and 0.03uF cap in parallel will work fine for a 0.05uF. These caps are not at all that critical in value.